Topics.md

Topics

System Design

Exercise:

• Design File Downloader Library: to redo
• Design Caching Library: to redo
• Design Image Library: to redo
• Design Chat app: to redo
  • ask ChatGPT
• Design Twitter Feed: to redo

Mock

• Discord group for finding partners
• List of recorded mocks

Resource:

• Building mobile app at scale: to read (very important)

How to support offline?

• Trello

  • Airplane Mode
  • Sync
  • Sync Failure Handling
  • Sync two id problem
  • Offline attachments
  • Sync is a two-way street
  • Display Sync State

• Azure

  • Data Caching and Synchronization: to watch

Handle Synchronization conflicts

• Azure: Handle Synchronization conflicts: to watch
• Google Doc: automerge, pullrequest

Polling

• Polling in spotty connection, or app runs into background

Functional Programming

Git

Design Pattern

• Design Notification Center

Data Structrure and Algorithms

• DFS
• BFS
• In-Order-BST
• BT
• Intervals
• Backtracking
• Two-Pointers
• Graph

iOS

Security

• Exploiting Common iOS Apps’ Vulnerabilities: to watch

Persistence

• Cache
  • NSURLCache

Swift

• Quizz: to review
• autoclosure
• frozen enum
• static func vs class func: static and class both associate a method with a class, rather than an instance of a class. The difference is that subclasses can override class methods; they cannot override static methods.
• decode an enum --> use struct (RawRepresentable) instead
• codable, decodable, RawRepresentable

Test

• How to call a set up method only once before running all tests in a test class? use override class func setUp()
• How to call a set up method only once before running all tests of all classes? use Principal class in info plist of Tests target more info

SwiftUI

• Navigation

CI/CD

Pipeline

• How does XCode generate a DerivedData hash?
• SwiftLint? What is the advantage of create a separate target for SwiftLint? for standardization, and also because you don't want to run swiftlint everytime you build your target (you only need to run it at some point, as a check, but not everytime, especially on the CI, that's too expensive)
• What is the aggregate target used for?
• Sonarqube?
• Keychain doesn't allow to use different accounts to access the same base url (like www.example.com, www.example.com/home, www.example.com/category, etc.) How do we overcome it? The answer is use a custom credential provider (in keychain). It's a bit more subtle than that, like, you can configure keychain to hold different credentials for full repo url-s, but we need an intermediate thing (like dev.azure.com/). The default macos keychain handler allows only base url (dev.azure.com), or full repo-url (dev.azure.com/../../../), but no intermediate ...and it has other disadvantages too
• Test Plan?

Others

• Design: Figma, Invision
• https://app.lokalise.com/